An overview of the Oyashio ecosystem

نویسنده

  • Yasunori Sakurai
چکیده

The Oyashio shelf region and the seasonally ice-covered areas north of Hokkaido are highly productive, supporting a wide range of species including marine mammals, seabirds and commercially important species in the western subarctic Pacific. The fishes include gadids, such as walleye pollock and Pacific cod, and subarctic migratory pelagic fishes such as chum salmon and pink salmon. It is also an important summer feeding ground for subtropical migrants such as the Japanese sardine, Japanese anchovy, Pacific saury, mackerels, Japanese common squid, whales and seabirds. In recent decades, some components of the Oyashio ecosystem (i.e., phytoplankton, mesozooplankton, gadid fish, and subtropical migrants) have shown changes in species abundance or distribution that are correlated with environmental changes such as the 1976/1977 and 1988/1989 regime shifts. The First Oyashio Intrusion moved northward from the mid-1960s until the late 1970s, when it moved southward until the 1980s, after which it returned to the north again after the mid-1990s. The sea-surface temperature in spring decreased after the late 1970s, increased after the late 1980s, and remained high during the 1990s. The extent of ice cover in the Sea of Okhostk also decreased during the latest warming in the 1980–1990s but has increased again since the late 1990s. This and other variabilities affect the Oyashio ecosystem and the surrounding region. r 2007 Elsevier Ltd. All rights reserved.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Recent Advances in Japanese Fisheries Science in the Kuroshio-Oyashio Region through Development of the FRA-ROMS Ocean Forecast System: Overview of the Reproducibility of Reanalysis Products

To address various fisheries science problems around Japan, the Japan Fisheries Research and Education Agency (FRA) has developed an ocean forecast system by combining an ocean circulation model based on the Regional Ocean Modeling System (ROMS) with three-dimensional variational analysis schemes. This system, which is called FRA-ROMS, is a basic and essential tool for the systematic conduct of...

متن کامل

An overview of the status, trends and challenges of freshwater fish research and conservation in Malaysia

Freshwater fish biodiversity is a precious natural asset in terms of economic, cultural and scientific interest. And yet, the inland freshwater ecosystem in Malaysia is declining at a far greater rate than terrestrial ecosystems in the tropics. What happened, and what is being done to address the crisis? This paper extracts findings from the latest literature and explores overarching issues per...

متن کامل

PICES XV Biological production, animal migration and ecosystem regime shifts in the Kuroshio and Oyashio Currents: Perspectives for sustainable use

s are sorted first by session and then alphabetically by presenter’s last name. Presenters’ names are in bold and underlined print. The Author Index includes all authors, co-authors, their paper IDs and page numbers. Some abstracts in this collection have not been edited and have been printed in the condition that they were received.

متن کامل

Characteristics of the zooplankton community in the Okhotsk Sea in autumn: A comparison with the Oyashio region

Based on the vertical stratified zooplankton samples collected during the autumns (September–December) of 1996 to 1998, vertical distribution, biomass, and community structure of zooplankton and calanoid copepods in the southern Okhotsk Sea were evaluated and compared with those of the same period in the Oyashio region. In terms of fauna, zooplankton in the Okhotsk Sea are similar to that in th...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2007